<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <select name="dd" id="ddd">
        <option value=1>d</option>
        <option value=2>d1</option>
        <option value=3>d2</option>
    </select>
    <script src="./innerType/6-boxing.js"></script>
    <script>
     document.getElementById("ddd").value=3;
    </script>
</body>
</html>